FXUS66 KPDT 240547

AFDPDT



Area Forecast Discussion

National Weather Service Pendleton OR

1047 PM PDT Thu Oct 23 2025



.UPDATED AVIATION.





.AVIATION...06Z TAFs...VFR conditions continue and will prevail

going forward. Active weather with periods of rain showers and

gusty winds will start to impact sites going through late morning

hours tomorrow through early afternoon. DLS/YKM will see

precipitation enter the area at around 18Z, with some other sites

(RDM/BDN/PSC) receiving PROB30 groups in the late afternoon hours

due to the axis direction of the system. 



Winds will start out light and variable but will become breezier

as we head through the later morning and early afternoon hours

with most sites developing 15-25 knot gusts by the late afternoon.

Sub-VFR conditions are possible (5-15% chance) with some of the 

heavier rain bands possibly bringing <6 mile visibility and/or low

CIG decks.







.DISCUSSION...



Key Messages: 



1. Widespread rain Friday and Saturday,



2. Mountain snowfall Saturday through Monday.



3. Breezy winds Friday turning windy Saturday into Sunday morning.



The weak upper ridge over the region will become broken down this

weekend as a cold pool aloft moves inland with an attendant 

atmospheric river, bringing orographic lift, rains and high 

elevation snow as early as Friday, and more widespread rains to 

the lowland regions again Saturday. Additional heavy snow amounts

will again compound the higher elevation snow amounts for the 

entire 3 day episode. 



The initial lead shortwave moves onshore Friday morning and 

overspreads the Interior Northwest through Friday evening. This 

initial wave can bring snow to the highest elevations of the 

Cascades Friday and Friday Night as the snow levels hover around 

6500-8000 ft, and dropping sharply Friday evening across the 

Washington Cascades to the 4-5kft layer. As the colder air arrives

with the second, more large scale shortwave and with westerly 

moisture transport Saturday, these more efficient snows will be 

largely confined to WA523 Lower Slopes of the Eastern Washington 

Cascade Crest, and OR509 East Slopes of the Oregon Cascades. Rain 

farther east in the lowland areas are limited to the Washington 

Cascades and eastern slopes Friday evening, however the next 24 

hours through Saturday evening, a widespread near two tenths to 

around a third of an inch QPF is projected by the NBM 50th 

percentile of members. Assuming a less robust episode develops 

with respect to moisture, the 25th percentile would still suggest 

at least close to a wetting rain of nine or ten hundredths of an 

inch across the Columbia Basin and central Oregon with more like a

quarter of an inch across the eastern Mountains. Lowlands precip 

should wane or become more intermittent in nature by Sunday with 

ongoing orographic lift promoting additional snows in the Cascades

and Wallowas. Fire weather will be enhanced, for a short period 

on Friday afternoon where combined probabilities for red flag 

conditions are running about 20 percent across Deschutes, 

Jefferson and Crook counties in the afternoon. Russell/71



&&



.PRELIMINARY POINT TEMPS/POPS...

PDT  43  69  44  61 /   0  10  80 100 

ALW  47  70  46  61 /   0  10  90 100 

PSC  41  65  41  61 /   0  20  60  90 

YKM  43  62  36  54 /   0  60  70  90 

HRI  42  64  43  62 /   0  20  70  90 

ELN  39  58  31  50 /  10  70  80  90 

RDM  39  68  37  55 /   0  40  80  90 

LGD  41  66  44  57 /   0   0  80 100 

GCD  42  70  44  57 /   0   0  80 100 

DLS  47  64  44  59 /   0  80  90 100 



&&



.PDT WATCHES/WARNINGS/ADVISORIES...

OR...None.

WA...None.

&&



$$



SHORT TERM...71

LONG TERM....71

AVIATION...95